A potential field approach to the modeling of route choice in pedestrian evacuation

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Collection, spillback, and dissipation in pedestrian evacuation: A network-based method

We present a method of predicting pedestrian route choice behavior and physical congestion during the evacuation of indoor areas with internal obstacles. Under the proposed method, a network is first constructed by discretizing the space into regular hexagonal cells and giving these cells potentials before a modified cell transmission model is employed to predict the evolution of pedestrian flow in the network over time and space. Several properties of this cell transmission model are explored. The method can be used to predict the evolution of pedestrian flow over time and space in indoor areas with internal obstacles and to investigate the collection, spillback, and dissipation behavior of pedestrians passing through a bottleneck. The cell transmission model is further extended to imitate the movements of multiple flows of pedestrians with different destinations. An algorithm based on generalized cell potential is also developed to assign the pedestrian flow. © 2010 Elsevier Ltd.postprin

Admissibility of a wide cluster solution in "anisotropic" higher-order traffic flow models

We analytically investigate a wide cluster solution and show that it is not admitted in some of the traffic flow models in the literature. For those traffic flow models that admit the wide cluster solution, the relationship between two important control parameters and the critical densities that divide an equilibrium solution into stable and unstable regions is thoroughly discussed in detail. We find that such wide clusters exist with a free traffic density in an unstable region, and with one or three critical densities. These results are different from the cases in the well-known higher-order traffic flow models of Payne and Whitham [H. J. Payne, "Models of freeway traffic and control," in Mathematical Models of Public Systems, A. G. Bekey, ed., Simulation Council Proc. Ser. 1, La Jolla, CA, 1971, pp. 51-61], [G. B. Whitham, Linear and Nonlinear Waves, John Wiley and Sons, New York, 1974], Kühne [R. D. Kühne, "Macroscopic freeway model for dense traffic-stop-start waves and incident detection," in Proceedings of the 9th International Symposium on Transportation and Traffic Theory, J. Volmuller and R. Hamerslag, eds., VNU Science Press, Utrecht, 1984, pp. 21-42], and Kerner and Konhäuser [B. S. Kerner and P. Konhäuser, Phys. Rev. E (3), 50 (1994), pp. 54-83]. © 2007 Society for Industrial and Applied Mathematics.published_or_final_versio

Numerical simulation of transient force and eddy current loss in a 720-MVA power transformer

Author name used in this publication: S. L. HoAuthor name used in this publication: H. C. WongVersion of RecordPublishe

Deprivation is associated with anxiety and stress. A population-based longitudinal household survey among Chinese adults in Hong Kong

BACKGROUND: Mental illness is a major disease burden in the world and disproportionately affects the socially disadvantaged, but studies on the longitudinal association of poverty with anxiety and stress are rare, especially in Asia. Using data from Hong Kong, we aimed to (1) assess the cross-sectional association of poverty with anxiety and stress at baseline, and (2) to examine whether baseline poverty and change in poverty status over time are associated with a subsequent change in anxiety and stress. METHODS: Data were obtained from two waves of a territory-wide longitudinal survey in Hong Kong, with sample sizes of n=1970 and n=1224 for baseline and follow-up, respectively. Poverty was measured with a Deprivation Index and income-poverty. Anxiety and stress symptoms were assessed using Chinese Depression, Anxiety and Stress Scale-21 Items. We conducted cross-sectional and longitudinal analyses on the association of poverty with anxiety and stress. OUTCOMES: Deprivation, but not income-poverty, was significantly associated with both outcomes at baseline. Increased deprivation over time was associated with greater score and increased risk of anxiety and stress. Persistent deprivation over time was associated with greater anxiety and stress, and increased risk of incident anxiety. INTERPRETATION: Deprivation could have significant independent effects on anxiety and stress, even after adjusting for the effects of income-poverty. Greater attention should be paid to deprivation in policymaking to tackle the inequalities of mental health problems, especially since stress and anxiety are precursors to more severe forms of mental illness and other comorbidities

Socioeconomic Patterns of COVID-19 Clusters in Low-Incidence City, Hong Kong

Although coronavirus disease (COVID-19) outbreaks have been relatively well controlled in Hong Kong, containment remains challenging among socioeconomically disadvantaged persons. They are at higher risk for widespread COVID-19 transmission through sizable clustering, probably because of exposure to social settings in which existing mitigation policies had differential socioeconomic effects

Lifestyle-modified mortality associated with air pollution: a time-series study

Health Services Research Fund & Health Care and Promotion Fund: Research Dissemination Reports (Series 9)published_or_final_versio

Social setting, intuition, and experience in lab experiments interact to shape cooperative decision-making

Recent studies suggest that cooperative decision-making in one-shot interactions is a history-dependent dynamic process: promoting intuition versus deliberation has typically a positive effect on cooperation (dynamism) among people living in a coop- erative setting and with no previous experience in economic games on cooperation (history-dependence). Here we report on a lab experiment exploring how these findings transfer to a non-cooperative setting. We find two major results: (i) promoting intuition versus deliberation has no effect on cooperative behavior among inexperienced subjects living in a non-cooperative setting; (ii) experienced subjects cooperate more than inexperienced subjects, but only under time pressure. These results suggest that cooperation is a learning process, rather than an instinctive impulse or a self-controlled choice, and that experience operates primarily via the channel of intuition. In doing so, our findings shed further light on the cognitive basis of human cooperative decision-making and provide further support for the recently proposed Social Heuristics Hypothesis

The Clinical Utility of SUDOSCAN in Chronic Kidney Disease in Chinese Patients with Type 2 Diabetes

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COVID-19 related health inequality exists even in a city where disease incidence is relatively low: a telephone survey in Hong Kong

Background: We examined whether COVID-19 could exert inequalities in socioeconomic conditions and health in Hong Kong, where there has been a relatively low COVID-19 incidence. Methods: 752 adult respondents from a previous random sample participated in a telephone survey from 20 April to 11 May 2020. We examined demographic and socioeconomic factors, worry of COVID-19, general health, economic activity, and personal protective equipment (PPE) and related hygiene practice by deprivation status. The associations between deprivation and negative COVID-19 related issues were analysed using binary logistic regressions, while the associations of these issues with health were analysed using linear regressions. Path analysis was conducted to determine the direct effect of deprivation, and the indirect effects via COVID-19 related issues, on health. Interactions between deprivation and the mediators were also tested. Results: Deprived individuals were more likely to have job loss/instability, less reserves, less utilisation and more concerns of PPE. After adjustments for potential confounders, being deprived was associated with having greater risk of low reserve of face masks, being worried about the disease and job loss/instability. Being deprived had worse physical (β=−0.154, p<0.001) and mental health (β=−0.211, p<0.001) and had an indirect effect on mental health via worry and job loss/instability (total indirect effect: β=−0.027, p=0.017; proportion being mediated=11.46%). In addition, significant interaction between deprivation and change of economic activity status was observed on mental health-related quality of life. Conclusion: Even if the COVID-19 incidence was relatively low, part of the observed health inequality can be explained by people’s concerns over livelihood and economic activity, which were affected by the containment measures. We should look beyond the incidence to address COVID-19 related health inequalities